Is Google planning an iris-scanning contact lens?

Google may be developing iris recognition for its smart contact lenses, if a recent patent is anything to go by.

According to papers held by the US Patents and Trademark Office, the California-based search engine giant successfully filed a 21-page patent for iris-scanning contact lenses which could be used to identify the wearer and used in conjunction with other devices, such as to unlock a smart phone.

It includes a number of diagrams and alludes to light sensors, which could potentially measure light filtered through the iris, linked to circuitry within or on the body of the lens.

Google simply states: "In various implementations, the contact lens can be employed in systems and/or methods associated with authentication and identification."

The latest news follows plans for a smart contact lens for diabetes which could measure glucose levels in the tears of the wearer, which the US company has said it plans to work on with Novartis-owned contact lens company Alcon.